1. Field of the Invention
The present invention relates to cooling plates for shaft furnaces, particularly blast furnaces, provided with a refractory lining. The cooling plates are composed of copper or a low-alloy copper alloy with cooling medium ducts, wherein the cooling plates are made from a wrought or rolled ingot, and wherein the cooling plates have on one side thereof, i.e., the front side, grooves for receiving refractory material.
2. Description of the Related Art
Cooling plates of the above-described type are disclosed in German Patent 29 07 511. In these cooling plates, the cooling ducts are provided in the wrought or rolled ingot in the form of vertically extending blind-end bores which are produced by mechanical deep drilling. Cooling plates of this type must have a relatively great thickness to make it possible to bore the cooling ducts without impairing the stability of the cooling plates. On the front sides as well as on the rear sides of the cooling plates sufficient copper material must remain in the areas of the bores in order to ensure that the cooling plates have sufficient strength. Consequently, very thick copper plates are required which are correspondingly very expensive because of the high price of copper.
Since the cooling ducts are produced by drilling into the cooling plates, only circular holes can be made. These circular blind-end bores have only relatively small surfaces at which the required heat exchange from the cooling plates to the cooling medium can take place. Consequently, only a poor heat transfer is achieved.